Brake



April 25,- 1939. A. o. WILLIAMS BRAKE 2 Sheets-Sheet 1 Filed June 2, 1938 N4 N W; M W5 d A W P M? April 1939- A. o. WILLIAMS 2,156,006

I BRAKE Filed June 2, 1938 2 Sheets-Sheet 2 A T TORNEY.

Patented Apr. 25, 1939 BRAKE Alfred 0. Williams, Battle Creek, Mich; assignor t Clark u pm nt Comp n Bat le e k, Mich., a corporationof Michigan A plication .lline g, 1938, Serial No. 211,418'

12'Claims'. This invention relates to brakes and braking systems, and is particularly concerned with the provision of a braking system for use in street cars, rail cars and other rail vehicles employing shoe type brakes engageable with the tread of the car wheels.

In the majority of rail vehicles of this general type now in use it has been customary to provide a transversely extending brake beam or brake rod which, at opposite ends, carries suitable brake heads supporting brake shoes toward or away from the tread surface of the car wheels. In most cases such brakes are applied by means of air under pressure directed against a piston which is 5 suitably connected to a crank arm or other mechanism for rotating the shaft with spring means operable to return the brake shaft to brake-released position upon release of the air pressure in the brake cylinder. v However, with such types of braking mechanism it is apparent that if there should be an accidental leak in the pressure line, or the air compressor in the vehicle should fail to function properly, there would be no means for applying the brakes and consequently the car would be without any braking means other than perhaps the braking eifect of the motor or the like. may result in serious danger due to the fact that the operator is not apprized of the defects in th,e 36 braking system, and consequently accidents may result due to failure of the brakes to fnnc-tion properly.

The present invention is concerned particularlt with the provision of a braking system which is automatically operable upon a defect in the air pressure system for setting the car brakes and thereby stopping the car, thus preventing any possibility of accident and at the same time apprizing the operator of the defective condition of the brakes.

One of the primary objects of the present invention is to provide a braking system of this type, which operates to rock the brake arm or brake :rod into brake engaging position upona decrease in the air pressure system. This mechanismis so constructed that it will result in positive setting of the brakes upon .such leakage in pressure, and will maintain the brakes set until the operator manually releases the mechanism :to

allow the car to be towed or moved to the desired repair station. Another feature of the present invention is :the provision of a suitable latching means which is normally'positioned so as to provide a rigid crank arm between :the brake'actuating mechanism and the brake beam, but which is manually r eleasable to permit a release of the brake beam so that it will return to brake-released position upon suitable manual operation.

Another feature of the present invention re.- sides in the provision oi a negative braking sys: tem of this type which is composed of relatively few parts, and which is capable of easy assembly and mounting upon car trucks and is mechansally actuated by spring means or the like en,-

heir independently of any control 9n the part of the operator, and responsive solely to, lie: eases pres ure in the p essure brakingsys: temln t e prefer ed form of the p esent intention prsisrebl smplo actuatin cy ind and p ton s n tmst an which a essure on the iston is th s l mle norma l ho d the brake control mechanism in inoperatiye position, bu an es s ss in su h P ess re rssul s he ston be ng ms ssl tswa -sl treks s ra in Ro ie, ti n y means s a re ativel h av s in $284: rie thin he cy inder The syl nds ssns rus iss itsel is 9 p ease sig a d is so a ang d as to be serrate e l hou ing f the b eak exi t! dinally o the t ust t point v bsa'm- P ab y h on rod has onne tion n h is on he d is assai lpslafi the .arcu s nging m ement a its 9 on the brake eam a i m es ape j; plying to b e l as g P sit on- O he -ob ec s and aq sntasssq msnrgs t in: vsniisn wil p ar mor A ull i on the i .92 s d d e rir s whic takes-is caesium;- s i h the c m an ng dr win s wil 5 1s:

closets th kill in the a t the Pa ticul r s u ian and er io o a rrsis t ssi-ft rm of e P esen in en ion In thedrawings:

i ure 1 a si r svatie nl ew nsst rria s ct o of one arm o he presen ii rsntion;

i -u e ;2 s an an vs s rati na n w the s n-- otion between th c nde an t brak b am hownin Land v s t Figure 3 is an enlarged side eleyational yiew of the portion of the mechanism shown :in Figure 2.

Conside in ow the draw ngs i deta an axle housing is indicated,generallyatgiandhasdhe axle shaft 6 extending therethrough in the usual manner. The shousin-g15 is provided withaiboss portion 11 forming a bolting ;face-.to which is see cured .the :bracket :8 :having the cyllndrioal sleeve portion ,9 adapted to receive the cylinder sleeve it, which may be welded or otherwise rigidly cured therein.

The cylinder sleeve ill at its upper end is adapted to extend into an annular recess 12 formed in the cylinder head l3, and is sealed with respect thereto by means of the lead gasket I4. The cylinder head 13 is suitably bolted as indicated by the bolts I5 to a flange l6 on the bracket, and the lead gasket is thereby compressed to seal the cylinder head 53 to the cylinder sleeve [0. A suitable fluid inlet port is provided in the head 13, as indicated at IT, and is connected through the tapped opening l8 to any suitable source of pressure supply, such as a compressor or the like carried by the car to which the truck is secured.

The truck itself may be of the general type shown in the copending application of Robert J. Burrows and myself, Serial No. D-74,505, filed January 24, 1938, although it may be equally well applied to any type of truck.

Disposed within the sleeve I0 is a piston head 26 having a suitable leather or rubber sealing member 22 secured over the head end thereof, and forming a tight seal with the internal wall of the'sleeve It). The piston head 26 is provided with the central journal portion 23 within which is mounted a cross beam member 24 having the suitable normally extending journal portion 25 to which is connected the sleeve end 26 of a piston rod 21. The rod 21 therefore has substantially universal support within the head 20, and is preferably enclosed within a second sleeve 29 which is secured to the head of the piston and which extends axially of the sleeve E0, and is guided for reciprocation conjointly with the head by means of the bushing 30 bolted, as indicated at 32, to the end plate 33 which is secured within the outer end of the cylinder sleeve in as by means of the annular weld 34.

Biased between the end plate 33 and the base of the piston head 20 is a relatively heavy coiled spring 35 which normally urges the piston head 20 to its full inner position, thereby tending to drawthe rod 21 inwardly of the sleeve 10. Preferably, the sleeve 25 is provided with a key member 36 which slides in a suitable keyway 37 formed in the bushing 30 to prevent rotation of the sleeve 29 relative to the cylinder i6, thereby preventing rotation of the head 20 within the cylinder sleeve which would produce undue friction and possibly result-inbinding on the spring 35.

The outer end of the rod 27 is threaded, as indicated at 40, and has mounted thereon a sliding block 42 having a sleeve member 43 extending therethrough upon which is pivotally mounted the yoke portion 44 of the arm 45. The block 42 is held inv position longitudinally of the rod 21 by means of the nuts 46 and the spring '41 encircling the rod and biased at one end against the washer 43 and at the opposite end against the block 42. The spring 41 prevents the block 42 from moving inwardly with respect to the rod 21, while the nuts 46 serve as positive abutments for the-block 42"to move the arm 45. conjointly with inward movement of the rod 27 under influence of spring 35.

'The arm is provided with a forwardly extending tongue portion 50 which is adapted to receivea pivot-pin 52 forming a pivot for the bifurcated ends 53 of a second arm 54 having the sleeve portion 55 welded or otherwise suitably secured to the brake beam or brake rod 56. will thus be seen that the arms 45 and 54 are connected by the pin 52 for relative pivotal movement, andthat the arm 54 in turn is connected to the transversely extending rod 56 whereby any movement of the arm 54 caused by its connection with the arm 45 will result in rotational move' ment of the rod 56.

The arms 45 and 54 are provided with coacting abutments 51 and 58, respectively, which are adapted to engage together to provide for limiting relative rotational movement of the two arms, and thereby forming the two arms into a single strut or crank member connected between the rod 56 and the piston rod 2'1. It will be apparent that an inward thrust caused by spring 35 on the piston and which tends to rotate the two arms 45. and 54 in a counter-clockwise direction about the center of rod 56 will have a tendency to break the abutting engagement at the point 5158 and cause the two arms to rotate with respect to each other about the pin 52.

In order to lock the two arms together, a suitable toggle locking mechanism is provided which comprises a rearwardly extending boss 60 on the arm 45 adapted to carry the pin 62 which is held thereon by means of the nut 63, and which has a suitable eye portion 64 adapted to receive a cross pin 65. Connected to the cross pin 65 is a pair of links 66 as shown more clearly in Figures 2 and 3, which extend downwardly on opposite sides of the hook portion 6'! formed as a rearward extension adjacent the top of the arm 54. Pivotally mounted between the links at the lower ends thereof is a toggle control member 68 mounted on the cross pin 69 and having a cam portion 10 adapted to engage under the hooked end of the portion 61 of the arm 54 to thereby force the links 66 against a rearwardly projecting boss 12 on the arm 54.

With this construction it will be apparent that the pins 65 and 69 connected by the links 66 form with the cam engagement indicated at 10 a toggle construction which, in normally latched position, is over center, the point of camming engagement of the member 68 with the hooked portion 61 lying outwardly of a line between the pins 65 and 69. This provides for latching the arms 45 and 54 together against possible relative movement about the pin 52 so that the two arms in elfect constitute but a single crank connected between the piston and the transverse brake beam.

In the operation of the mechanism thus far described, under normal operation, the cylinder head above the piston 20 is preferably filled with air or other fluid under pressure, such as to force the piston outwardly of the sleeve H) to thereby compress the spring 35 and thus hold the connection arms 45 and 54 in brake releasing position due to the spring 41 abutting against the block 42. Upon normal actuation of the brakes by the control means, the transverse rod 56 will be rotated slightly in a counter-clockwise direction by forward movement of the block 42 under influence of spring 35, and will also cause a slight raising of rod 27 about its pivot 26 within the sleeve 29. The control means will release the braking system by admitting pressure to cylinder I0, compressing spring 35 to thereby restore the mechanism to the position shown in Figure 1.

However, if any leaks should develop in the braking system or if the pressure system should fail to hold pressure, the pressure within the cylinder sleeve l0 above the piston will decrease, and consequently the piston 20 will move inwardly of the sleeve l0 under the influence of spring 35. This results in conjoint inward movement of the sleeve. 29rand the piston rod 21, and the nuts 46 will thereby be drawn to the left as shown in Figure 1 moving the block 42 to the left, and inasmuch as the arms. 45. and 54 are locked together, will cause rotation of the rod 56 to move the brake shoes carried thereby into pressure engagement with the tread of the wheels. This locks the car against movement and immediately apprizes the operator that the braking system has become defective, and at the same time prevents movement of the car which might result in accident or serious danger to the occupants of the car due to a faulty brake system.

However, it is not desirable that the car. remain in stopped position upon the tracksuntil suitable repairs can be made, to the pressure brakingsystem, and for that reason, I have provided releasing mechanism for the emergency brakes which can be manually actuated by the operator in order that the car may be towed to a suitable repair station or the like. In the form of the invention shown, this comprises the toggle looking means which may be manually released by the operator by inserting a suitable crowbar or the like in the space 13 between the lower end of the cam member 6.8; and the boss 12 and prying the cam member outwardly away from the boss to thereby move the cam point 10 into alinement between the pins 69 and 65 resulting in the toggle joint being broken and the links 66 swinging free into the position shown in Figure 3. When this occurs, the hooked portion 61 of the arm 64 is released, and inasmuch as the spring pressure on the arm 56 is normally tending to rotate this arm in a clockwise direction, the two arms will spread apart by pivotal movement about the pin 52 into the position shown in Figure 3 thereby allowing the arm 56 to rotate back to brake-released position, while the arm 45 is still maintained in the position to which it has been actuated by the spring 35 and will remain in such position until the cylinder Ill is again under pressure.

When the pressure is again admitted to the cylinder 10, the piston 20 moves outwardly moving the arm 45 outwardly and bringing the abutments 5! and 58 toward each other. Thecam point may then be placed under the hook 5'! and the lower end of the cam member 68 swung around to reset the toggle mechanism for locking the arms 45 and 54 against relative movement. The mechanism is then reset in position to be automatically operated upon a defect in the air pressure braking system to again set the brakes to prevent operation of the car until such time as they are manually released.

If desired, the pin 69 may have an extension which is squared in section as indicated at 14, and a suitable socket wrench or the like may be engaged with this squared end of the pin to rotate the cam ID for releasing the toggle connection to allow the brakes to return to released position.

It is therefore believed apparent that I have provided a novel type of braking mechanism which will automatically set the brakes of the car whenever a defect occurs in the conventional pressure braking system. Also, the mechanism is capable of release by the operator to allow the car to be towed to a repair station and upon repair of the braking system, the system may be reset for automatic operation by re-engagement of the toggle mechanism.

I am aware that a number of changes may be made in the .details of the construction and assembly of the parts herein disclosed in the illustrated embodiment of the invention, and I'therefore do not intend to be limited to the'particula'r details shown and described, but only insofar as may be defined by the scope and spirit of the appended claims.

I claim:

1. The combination, with a brake'beam adapted to carry shoe brakes, of an arm secured to said beam, a second arm pivotally secured to said first arm and having abutting engagement therewith limiting rotation in one direction, toggle locking mechanism locking said arms against rotation-in the opposite direction, pressure means normally holding said arms in brake releasing position, and spring means operative upon release of said pressure means for rotating said arms conjointly into brake applying position, said toggle mechanism being manually releasable to unlocksaid arms for relative rotation effecting release of said brakes.

2. In combination, a brake beam, an arm rig.- idly connected thereto, a secondv arm pivotally connected to said first arm, toggle means locking;

said arms against relative movement, a piston rod connected to said second arm, a cylinder for said rod, spring, means in said cylinder normally urging said rod toward brake-applying position and held retracted by air pressure, and manually operable means for releasing said toggle means to unlock said arms for allowing said brake beam to move to brake-releasing position independently of said piston rod.

3. In combination, a brake beam, an arm rigidly connected thereto, a second arm pivotally supported on said first arm, said arms having cooperating abutments preventing pivotal movement in one direction, a pair of links carried by one of said arms, a cam extension carried by the other arm, a cam lever carried by said links and engaging said extension for locking said two arms against relative movement in the opposite direction, and means connected to said second arm for actuating the same to rotate said beam.

4. The combination, in a rail truck of an axle housing having a bracket thereon, a cylinder supported in said bracket, a piston in said cylinder having an extending piston rod, spring means in said cylinder normally urging said piston toward the head end thereof, a jointed brake arm connected to said piston rod, and manually releasable toggle means for locking said arm as a rigid lever.

5. The combination, in a rail truck, of an air cylinder having a piston therein, a sleeve in said cylinder connected to said piston, a spring encircling said sleeve within said cylinder and normally urging said piston toward its inner limiting position, a piston rod connected to the piston and extending outwardly through said sleeve, a jointed brake lever connected to said rod, and toggle means for latching the joint in said lever to hold said lever rigid.

6.The combination, in a rail truck, of an air cylinder having a piston therein, a sleeve in said cylinder connected to said piston, a spring encircling said sleeve within said cylinder and normally urging said piston toward its inner limiting position, a piston rod connected to the piston and extending outwardly through said sleeve, a pair of brake lever arms pivotally connected together, one of said arms being connected to said rod, and toggle means for latching said arms to prevent relative movement therebetween.

7. In combination, in a rail truck having a jointed brakelever means secured to said beam, a brake cylinder having a piston connected to the free end of said lever means, and manually releasable toggle means for latching said lever means to form a rigid arm.

8. The combination of claim 7 wherein said piston is normally urged toward brake applying position in said cylinder and is held in brake released position by fluid under pressure.

9. In combination, in a rail truck having an axle housing, a brake cylinder supported on and extending normally thereto, a brake beam extending parallel to the axle and having a jointed brake lever projecting therefrom substantially normal to said cylinder, a piston in said cylinder normally urged toward brake app-lying position and connected to said lever, and toggle means for releasing the joint in said lever to release the brake beam independently of movement of said piston. I

10. In combination in a rail truck having an axle housing, a brake cylinder supported on and extending normally thereto, a brake beam extending parallel to the axle and having a jointed brake lever projecting therefrom substantially normal to said cylinder, apiston in said cylinder normally urged toward brake applying position and held in brake released position by air pressure, said piston having a rod adjustably connected to said lever, and manually releasable toggle means for maintaining the joint in said lever against collapse.

11. Brake lever means for a rail truck connected between a brake actuating piston rod and a brake beam, comprising a pair of arms, one connected to the rod and the other to the beam, a pivotal connection between said arms, and toggle means normally latching said arms together for conjoint movement as a rigid lever.

12. In a rail truck having a brake beam and a brake actuating piston, lever means therebetween comprising a pair of arms jointed together and having cooperating abutments limiting relative movement of the arms in one direction, and toggle means latched between said arms adjacent said abutments for preventing separation thereof to prevent relative movement of said arms in the opposite direction.

ALFRED O. WILLIAMS. 

